Don't Leave Me
by eyeslikeashowroom
Summary: Bellatrix is out of Azkaban, and gets reunited with her sister... in more ways than one. Sorry I suck at summaries, please review! WARNING: Blackcest, femslash. Rated M for sex & language.


**So I worked really hard on this. I don't think I'm very good at writing sex scenes, but I tried, hehehe! Anyway, it's Blackcest & femslash so if you don't like, please don't read. Not sure if this is a oneshot or if I'll continue. Please review and tell me what you think!**

"Cissy." Bellatrix's low voice floats across the dim, moonlit bedroom, reaching Narcissa and curling around her like something all too familiar, yet something sinister. She sits up, eyeing the silhouette of Bellatrix's thin form in the doorway, squinting against the bright light pouring in.

"What do you need, Bella?" Narcissa asks, her voice quiet yet demanding. "As I mentioned earlier, I'm feeling a bit ill." Bellatrix had come to stay at the Malfoy's just a couple days earlier, and since the time she had appeared suddenly in the middle of their living room (not even apologizing in the least for her rude entrance), Narcissa hadn't been able to speak a word to her sister. With one look at the raven haired beauty, all of the dark secrets they held in their past sprung up immediately, and Narcissa had bit her lip and stared at her sister, remembering how years ago Bellatrix had been her whole world, and the only person she thought she would ever love.

"You haven't spoken a word to me since I arrived," Bellatrix murmurs, her voice decidedly softer than Narcissa has heard it in a long time. "I would expect this coldness from Lucius, but certainly not from my own sister."

"Please, Bella," Narcissa replies, and her tone is almost bitter. She's not sure if she'll ever forgive Bella for leaving her, for choosing Rodolphus over her, the Death Eaters over her, Voldemort over her. For choosing everyone in the whole world over _her_. "Just listen, and leave."

And then Bellatrix is angry, slamming the door and stalking over to where Narcissa is sitting on the bed, leaning down and gripping her sister by the arms forcefully. Deep inside Narcissa has missed this forcefulness, missed the maddening anger that fills Bellatrix's eyes when Narcissa talks back to her.

"No, _you_ listen," Bellatrix hisses, sitting down and yanking on Narcissa's arms, tugging her sister closer until their noses are almost touching. "I won't take this from you." Her voice takes on a gentler tone, the fingers around Narcissa's arms loosening considerably. "I've missed you," she whispers, brushing her lips against Narcissa's ear, smirking when she feels her sister stiffen.

Narcissa is slammed with the childhood memories of her and Bellatrix. The time when she was 12 and Bellatrix was 16, and Druella had been being particularly cruel one night. Narcissa remembers how Bellatrix slipped into bed behind her, taking caution not to aggravate the cuts on Narcissa's back due to their mother's punishments. How she kissed away the tears streaming down Narcissa's face, and how she kissed some other things too. And how that was the first time Narcissa realized she was completely in love with her older sister, and she didn't think that she would ever fall out of it.

Narcissa says nothing, her icy eyes catching Bellatrix's dark ones in a heated gaze.

"What's wrong with you?" Bellatrix explodes, her anger getting the better of her.

"Unless you'd like Lucius and Draco to come up here and see what's going on," Narcissa replies coldly, "I suggest you keep your voice down."

Bellatrix's eyes widen as she stares at Narcissa. All she remembers as she looks at the fair-haired beauty is young Narcissa, the Narcissa that would do anything and everything as long as it pleased her oldest sister. The one who would listen to whatever Bellatrix told her. She doesn't recognize this Narcissa, the one with a smart mouth whose gaze doesn't falter and whose lip doesn't tremble in the face of Bellatrix's anger. "What did I do?" Bellatrix asks, her voice quiet. Narcissa doesn't miss the underlying anger, the madness simmering just below the surface of her sister's voice. "What did I do to make you hate me, Cissy?"

"I could never hate you, Bella." And it's true, because as much as Narcissa wants to, she just can't.

Bellatrix reaches out and strokes Narcissa's hair, her touch the lightest that Narcissa has ever felt it in her life. "Then why?" "You left me," Narcissa blurted, and suddenly she's 12-year-old Cissy again, watching as Bellatrix grows up and changes, starts noticing whom she's hanging around. Suddenly she's that insecure little girl that Narcissa has always wished she could forget.

Bellatrix doesn't have an answer to that, not really. "I'm here now."

It'll have to suffice.

And it does, for Narcissa. And then her lips are crashing against Bellatrix's, hard and without warning.

Bellatrix pulls away slightly, eyes hooded and smirk predominant on her face. "Eager there, are you little Cissy?" Her hand slides up and tangles in Narcissa's hair, remembering when every night used to be like this, when she was able to touch the perfection that was her sister every day.

"God, I missed you." And the Narcissa that Bellatrix remembers is back, if only slightly. Narcissa bites her lip and gazes at Bellatrix with the love she had been hiding ever since her sister had come to this house.

"Finally," Bellatrix replies, relishing in Narcissa's admission. She leans and brings her lips to Narcissa's, chewing softly on her little sister's bottom lip as Narcissa's fingers grip at her hair and scratch her scalp. "I need you," she whispers, hearing Narcissa's breath catch at the hoarseness in her voice.

"Take me," Narcissa murmurs back. Her fingers tighten around Bellatrix's hair and the older sister growls softly, biting her lip and trying to force the violent thoughts out of her head. Narcissa has always brought Bellatrix's cruel qualities out without even trying. But she doesn't want this time to be like that, to be harsh and rough and mean. Bellatrix wants it to be special.

"You know what happens when you say things like that to me," says Bellatrix quietly, glancing down at her hands. She glances back up at Narcissa.

Narcissa watches her silently for a moment. Then, "I know."

Bellatrix isn't sure if Narcissa knows what she's allowing, what she's encouraging. But her sister has never been unintelligent.

"Take this off," is Bellatrix's first command as she fingers the lacy nightgown that Narcissa is clothed in. Narcissa gets up on her knees and tugs it off, feeling Bellatrix's eyes on her body like a million soft caresses. Bellatrix takes her clothes off as well, distractedly, her eyes glued to Narcissa's pale, perfect skin. Her little sister just looks so small and perfect and fucking breakable.

Bellatrix _wants_ to break her.

It's not long before she's touching, hands reaching out and tugging Narcissa towards her, grasping hips and scratching skin and pulling hair.

Narcissa reaches for her wand on the bedside table and flicks it, locking the door so they're absolutely not interrupted.

Bellatrix's fingers skim lightly across the top of Narcissa's red, lacy underwear. "Naughty girl, aren't you Cissy?" she drawls, smirking. Narcissa blushes, leaning forward and pressing her lips against Bellatrix's.

"No," she breathes, because inside, she's always wanted to be good girl for Bella.

"Your undergarments suggest otherwise." Bellatrix runs her hands up and down Narcissa's sides, roaming the perfect skin in a blatantly possessive manner. "Do you like to get all dolled up for Lucius in these?" Her hands travel upwards and cup Narcissa's breasts through her bra, immediately causing the blonde's nipples to harden almost painfully.

Narcissa's sex life with Lucius was existent, but not very much so. "No," she whispers against Bellatrix's insistent lips. "I bought them just because I like them."

"No fun, sister," Bellatrix replies, taking Narcissa by the shoulder and holding her away so she can stare in her eyes. "Will you do a show for me, and take them off?"

"No." The answer is immediate and delivered without hesitation. Narcissa's never been an exhibitionist in the least, and she won't be now.

She watches as Bellatrix's face changes, as her eyes grow colder and her sneer grows larger. Narcissa blinks, and braces herself.

Then, Bellatrix's fingers are clasped around the fabric at the front of her bra, and she's speaking in that hoarse voice that makes Narcissa's underpants dampen when she least wants them to.

"Bad girl," Bellatrix admonishes, pulling slowly on the flimsy bra until it snaps away from Narcissa's body. Narcissa stares as it falls brokenly to the bed, just another reminder of the way Bellatrix likes to break things.

Bellatrix leans forward, tracing a finger along Narcissa's jaw, taking care not to use her nail because if she starts scratching her sister's pale, delicate skin, she won't be able to stop. "You know that you're not supposed to defy me, Narcissa. Did you forget that?" Her eyes are dark with the need to control, the need for power. "Did you forget what I taught you all those years ago, little sister?"

Narcissa hasn't forgotten, and never will. Because as much as Bellatrix protected her when she was little, Narcissa still has the burn marks on her body from Bellatrix's wand, the scars that remind her how Bellatrix's protection was a curse as well as a blessing.

"Things are different now." Narcissa knows what she's toying with, what she's getting herself into. Bellatrix has never been in the right state of mind, and her time in Azkaban had made it a hundred times worse. Narcissa could see her sister's mood shifting and she knew it wouldn't take much to set Bellatrix off.

"You think so?" Bellatrix's voice is sickly sweet and Narcissa knows that's trouble. She's alternating between telling her older sister to stop and wanting Bellatrix to fuck her brains out.

"Bella. I want..."

"What?" Bellatrix's fingers close around Narcissa's throat. She brings Narcissa's face closer to hers until their lips are touching. "What would you like, Narcissa?"

Narcissa glances down as Bellatrix's hand run across the top of her panties, splaying out against her pale stomach. The long slender fingers dip inside the lacy fabric, brushing through the neatly trimmed hair underneath. Bellatrix sighs as she feels Narcissa's wetness coat her fingers immediately.

"Somebody's excited," Bellatrix sings, smirking down at her sister. This brings back so many memories of sneaking into Narcissa's bed in the middle of the night and watching as the blonde shivers and cries out, coming hard against Bellatrix's palm, and then their promises to each other that they'll never tell anyone their dirty little secret as long as they live.

"Please," gasps Narcissa. Her hips arch up, searching for more of the delicious contact that Bellatrix has teased her with. She doesn't want to tell her sister what she wants, what she _needs_, because Bellatrix already has so much of an advantage over her, always has.

"Tell me, Cissy." Bellatrix takes one hand and stills Narcissa's hips, her fingers brushing against the blonde's entrance and then resting there as she eyes her little sister.

Narcissa stares back, her eyes begging Bellatrix not to make her do this. What they're doing already makes her feel so wrong, so dirty and sinful. To voice her desires in words would add even more to the guilt Narcissa feels inside because of the things her and Bellatrix do.

Bellatrix slides her fingers away from Narcissa's spot, trailing them upwards and out of her panties. "_Narcissa_." Narcissa flinches at the sharp warning.

"I want you to make love to me," Narcissa blurts, her face turning red immediately. She glances down at her hands, picking at a loose thread in the bedding furiously. Bellatrix takes her by the chin and forces their eyes to meet, her cocky smirk hitting Narcissa in the gut like a punch.

"Tsk tsk, darling," Bellatrix trills as she brings her other hand up Narcissa's body and rests it lightly against the swell of her breast. She doesn't like to think of this as _making love_, because she's corrupted Narcissa ever since they were kids, and she doesn't want Narcissa thinking this is normal, that it's something to become attached to and to cherish. Nobody should fuck and use and take advantage of their little sister and then call it 'making love'. "You want me to what?"

Narcissa swallows, forcing down the hurt feelings and disappointment. She loves Bellatrix with all her heart, wants to make love to her, not just fuck and then try to forget about it in the morning. That's not enough for her. "Fuck me."

"That's a girl," Bellatrix smiles, and Narcissa's reward is a light slap to the face. Bellatrix's foreplay has always been rough, and Narcissa hisses lowly in pleasure as Bellatrix's hand makes contact with her cheek. She wants this, no matter how horrible and degrading and awful it is. She wants this, and she wants Bellatrix.

Bellatrix never likes to waste time, and immediately she's taking Narcissa by the throat, pushing her back against the bed, and then holding her there. Once again, she slips her hand into Narcissa's underwear, pulling lightly at the soft hair and skin there. She leans up and kisses Narcissa deeply, her middle finger sliding into Narcissa's wet center with unimaginable ease. Bellatrix inhales sharply when she feels how wet Cissy is, thinking about how it's all for her.

"Yes, Bella. _Fuck_. Oh shit," whispers Narcissa, her cheeks burning as she hears herself utter the profanities. She has always disliked using vulgar words, but she says more curses in her nights with Bellatrix than she's ever thought possible.

"You're so _tight_, Cissy," Bellatrix moans, forcing two more fingers into Narcissa. She rotates her wrist and watches Narcissa's hips buck as Bellatrix's fingers twist inside of her. They both sighs at the sounds emitted from their act reaches their ears. "I forgot," Bellatrix starts, momentarily distracted by the obscene sound she's making as her fingers move in and out of Narcissa. She begins again. "I forgot how tight you were. How velvety and soft."

"_Harder_," Narcissa breathes through clenched teeth. "Faster, Bellatrix."

Bellatrix calls the shots, and they both know it, but she finds her fingers complying with Narcissa's demands. The fingers on her other hand tighten around Narcissa's throat, reminding the blonde that they're there. Narcissa swallows thickly, feeling her flow of air lessen but not particularly disliking it. She arches her back, rapidly getting closer and closer to her climax.

Bellatrix stares down at her little sister. "You're beautiful, Narcissa," she purrs, leaning and enclosing one of Narcissa's nipples with her plump lips. She sucks eagerly on the hardened peak, Narcissa's answering moans hitting her right between the legs. "Sweating and arching like the little whore that you are."

"_God_." Narcissa shivers, her chest heaving into Bellatrix's mouth as she inhales deeply.

"You are just a little whore, aren't you?" Bellatrix says, biting down on Narcissa's nipple until she cries out loudly. "My own little sister, the biggest slut that I know. But you're not a slut for everyone, baby. Of course not." She lets Narcissa's breast out of her mouth with a wet _pop_, staring at Narcissa until the blonde focuses her eyes on her as well. Bellatrix stares into the icy blue orbs, the way they have trouble focusing and staying open. Maintaining eye contact, she runs her tongue between Narcissa's breasts lightly, possessively. "You're _my_ slut."

Naricissa arches her back again, so _very_ close to orgasm. Bellatrix stares down at her sister's pale body, wanting to grab her wand and utter "_Crucio_", so she can watch Narcissa thrash and spasm and _drip_, for her. Bellatrix wants to hear her little sister scream, wants to watch the sudden pain flash across her face. She gets goose bumps just from thinking about it.

When Bellatrix's thumb presses against her clit, Narcissa lets herself go. She is a bit embarrassed, knowing that this is the quickest orgasm she's experienced when being with Bellatrix. But the long, hard years without her sister's touch had left her empty and longing and it hadn't taken much to bring her over the edge. She cries out loudly, back arching and arm reaching out to grasp Bellatrix by the shoulder. Bellatrix watches her as her eyes roll to the back of her head and her hips pump up over and over again. She keeps touching Narcissa until her touches cause Narcissa to spasm from sensitivity, pressing once more against her clit for good measure and then removing her fingers.

Narcissa cups Bellatrix's cheek. "Let me kiss you." Bellatrix allows it, loosening her grip on Narcissa's throat so the blonde can sit up and press their lips together. Narcissa trails her fingers down Bellatrix's flat stomach, her other hand tangling in Bellatrix's long, unruly dark hair. "Lay down." Bellatrix listens and Narcissa tugs her big sister's panties off, discarding them carelessly on the side of the bed. She runs her hand along the bare skin underneath them. "You shaved it all?"

"It grew longer when I was in Azkaban," Bellatrix replies, looking away as she once again remembers her time _there_. "I couldn't trim it. And I didn't like it, so when I got out I shaved it all off. Are we going to sit here discussing pubic hair or are you going to give me what I want?"

Narcissa bites her lip, immediately slipping her index finger inside of Bellatrix. She would always give Bellatrix what she wanted. Bellatrix moans with pleasure and reaches out to grip Narcissa's breast, and then her shoulder. Her nails dig into the flesh there so hard that they puncture it, and she hisses softly when she feels the wetness surround her fingertips. Her orgasm is rapidly approaching faster than Narcissa's did, and Bellatrix digs her nails in harder. She uses her other hand to once again grasp at Narcissa's throat.

"Fuck yes," she groans, closing her eyes and grinding her hips into the air as Narcissa adds three fingers and increases her speed and depth all at once.

"I love you, Bella," Narcissa whispers, staring down at Bellatrix as she writhers underneath her. "With all my heart. I'll do anything for you, forever. I promise."

Bellatrix hisses again at Narcissa's words, her fingers squeezing her sister's neck tightly. She feels Naricissa's nails dig into her stomach, knows it's too much. Her eyes pop open and their eyes meet, Narcissa's calm and accepting and unafraid.

It destroys Bellatrix, because she knows she's a worthless piece of shit that deserves nothing, and Narcissa would _die_ if it meant making her happy.

"Distract me," she mutters, her eyes leaving Narcissa's for a moment while she stares up at the ceiling, then snapping back to her sister's. Her voice rises. "_Distract me_, Narcissa."

Narcissa moves her head and Bellatrix's fingers loosen, allowing Narcissa to bend down until her nose is pressed against the smooth skin of the area between Bellatrix's thighs.

Bellatrix nearly screams when she feels Narcissa's hot mouth on her, digs her nails into her palm as she feels her sister's tongue lick lightly along her slit. Narcissa swirls her tongue around Bellatrix's clit, bringing her hand up and slipping two fingers inside of her again. She pumps in and out as she nips lightly at Bellatrix's button, Bellatrix's moans encouraging her on.

"I'm close Cissy. Oh, shit, I'm gonna come. For you." Bellatrix clenches a hand in Narcissa's light hair. " I'm gonna come for _you_."

Narcissa stop licking for a moment, rests her nose against Bellatrix's clit and breathes in deeply. "Just tell me one thing," she begs, her voice muffled but loud enough. "_Please_, Bella. Before I finish. One thing."

Bellatrix sits up and tugs Narcissa up to her, cupping her cheek and staring at her with hooded eyes. She presses their lips together softly, lightly. Narcissa would call it loving, if she didn't know Bellatrix better.

"I love you, Narcissa," Bellatrix utters the long awaited words, watching Narcissa closely, wanting her to know that this is _real_. "I love all of you, every part of you. I couldn't stop thinking about you when I was in Azkaban. I missed you so much, Cissy. You're all I thought about." She kissed Narcissa again, slipping her tongue between Narcissa's lips and letting their tongues tangle together for a moment before she broke away, breathing shallowly. "Whatever you need me to do, I'll do it. I'll be here to protect you. I love you with all that I have, little sister. And I'll love you forever. I promise."

Naricissa doesn't tear her lips away from Bellatrix's, instead finishing her sister off with her fingers and knowing that Bellatrix won't mind. Her sister jerks, arching her body into Narcissa and crying out. Narcissa holds her as she spasms, her mouth running along Bellatrix's neck and marking her everywhere she can. She gasps as Bellatrix digs her nails into her back, dragging them down her back slowly as she comes down from her high. Bellatrix lets go of her and flops back down on the bed, staring up at the ceiling with glazed eyes. Narcissa brings her fingers up to her mouth, slowly sucking Bellatrix's juices off each one. Bellatrix notices this, sighing in contentment as she watches her sister.

"You're such a good girl, Cissy," she murmurs, reaching a hand out to Narcissa and drawing her closer. "Lay down." She does and Bellatrix leans up on her elbow and turns on her side so she's facing Narcissa, one hand resting on Narcissa's stomach and the other running lightly through her blonde locks. Narcissa purrs in contentment; she loves it when Bella calls her a good girl.

"It wasn't just the sex talking, was it Bella?" Narcissa asks quietly, her voice small. She closes her eyes, anticipating Bella's answer, trying to brace herself for it. Bellatrix hardly stays nice for long after the sex, and over time, the pain of being pushed away when she tried to cuddle afterwards became less hurtful for Narcissa.

"No," Bellatrix answers immediately, and Narcissa opens her eyes in confusion. This isn't how this is supposed to go.

"I missed you, Cissy. And I love you, too much for my own good. Too much for _your_ own good." Bellatrix sighs. It's not good for her to love Cissy the way that she does, and they both know it. "I meant every word that I said."

"Me too." Narcissa doesn't have much else to say.

Bellatrix smiles and presses a kiss to Narcissa's forehead before she lies down, telling Narcissa to turn so that they're spooning and Bellatrix can reach around and rest her hands on her sister's stomach. "Good girl."

Narcissa falls asleep with the words pounding into her head. She hopes with all her heart that Bella won't leave her again.


End file.
